Manufacture of diaminodiaryldialkylmethanes



Patented July 6, 1926.

UNITED STATES.

PATENT OFFICE.

ASSIGNMENTS, TO GRASSELLI DYESTU COBPOBATION OI! DELAWARE;

FF CORPORATION, OF NEW YORK, N. A.

MANUFACTURE OF DlIAMINODIARYLDIALKYLMETHANES.

li'o Drawing. Application filed September 18, 1923, Serial No. 668,711,and ii Germany September 29,1928.

I have found that diaminodiaryldialkylmethanes are obtained by causinprimary aminobenzenes with an'unoccupie para-pm sition, in the form oftheir salts and in aqueous solution to react upon aliphatic ketones.

The simplest representative of this class of bodies, viz thediaminodiphenyldimethylmethane, which may be obtained from aniline andacetone, corresponds to the formula:

a c 4 o r" a is u z 'The analysis gives the following results:

Found. ulatod C :79.58% 79.65% H: 7.95% 7.96% N=12.44% 12.39%

The diaminodiaryldialkylmethanes form an important startin material forthe preparation of dyestu s of difierent kinds.

Ewample.

370 parts of aniline are dissolved with the required quantity ofhydrochloric acid in about 1500 parts of water, then thereare added '60parts of. acetone and the whole is heated for six hours in a vesselunder pressure to about 120-150, C. The mixture having'cooled down, itis made alkaline with caustic soda, sodium carbonate or uicklime, theexcess of aniline is driven off y water vapour, and the remaining rawmaterial crystallized from boilin water. Thus the diaminodiphenyldimethymethane is obtained in the form of colourless, needle-like crystalsmelting at 132 C. It Is soluble in diluted mineral acids, readilysoluble in the common organic solvents, insoluble in cold water butslight-l soluble in boiling water.

According to t e same process there may be obtained from o-toluidine andacetone the diaminodi-o-tolyldimethylmethane (meltin point 71 C.), fromaniline and methylethy ketone the diaminodiphenyhnethylethylmethanemelting at 78.

Following the same. process there may be obtained from acetone ando-anisidine the di-o-anisyl-dimethylmethane melting at 32 0., fromo-phenetidine and acetone the liquid di-o-phenetidyl-dimethylmethane.

The parts by weight of the starting materials in the above example maybe widely modified; instead of hydrochloric acid other acids, e. g.sulphuric acid, may be used.

By the term a primary aminobenzene I understand in the description andthe fol lowing claims the aminobenzene itself or its derivativescontaining the substituent in the nucleus.

Having now described my invention what I claim 1s:

1. As new products the diaminodiaryldialkylmethanes of the generalformula:

an aryl residue, substituted or not, which are colorless substancesmelting without decomposition, insoluble in cold water and alkali,slightl soluble in boiling water, and readily solule in the commonorganic solvents and mineral acids.

2. Process for reparing diammodiaryldialkylmethanes which consists incausing a primary aminobenzene with an unoccupied para-position in theform of its salts to react upon aliphatic ketones.

ture.

BENNO HOMOLKA.

In testimony whereof, I afiix my signa-

